大约有 40,000 项符合查询结果（耗时：0.0533秒） [XML]
Detecting an undefined object property
...is the special value `undefined`");
}
To check if an object does not actually have such a property, and will therefore return undefined by default when you try and access it:
if(!o.hasOwnProperty('myProperty')) {
alert("myProperty does not exist");
}
To check if the value associated with an i...
How to get a complete list of object's methods and attributes?
...butes, the short answer is: no. The problem is that the attributes are actually defined as the arguments accepted by the getattr built-in function. As the user can reimplement __getattr__, suddenly allowing any kind of attribute, there is no possible generic way to generate that list. The dir functi...
How to override and extend basic Django admin templates?
...ound a nice template loader on djangosnippets.org that makes this easy. It allows you to extend a template in a specific app, giving you the ability to create your own admin/index.html that extends the admin/index.html template from the admin app. Like this:
{% extends "admin:admin/index.html" %}
{...
How to get current time and date in Android
...
+1 This was very helpful. Being new it's all these little tidbits we need ... I'm using Calendar to get the Julian date. Much easier than getting milliseconds and figuring out if the value equals today ;)
– Bill Mote
Apr 6 '11...
How to handle multiple cookies with the same name?
...nger paths are listed before cookies with shorter paths.
NOTE: Not all user agents sort the cookie-list in this order, but this
order reflects common practice when this document was written, and,
historically, there have been servers that (erroneously) depended on
this order.
There i...
How to fix Git error: object file is empty?
... the .git directory and run find . -type f -empty -delete -print to remove all empty files. Eventually git started telling me it was actually doing something with the object directories:
nathanvan@nathanvan-N61Jq:~/workspace/mcmc-chapter$ git fsck --full
Checking object directories: 100% (256/256)...
SQL error “ORA-01722: invalid number”
...
Also notice that manually complete a field with "(null)" will give you that error. If the defaul is null and you don't complete it will auto-complete with (null) but it is not the same when you type it.
– bogdan.rusu
...
When to use MongoDB or other document oriented database systems? [closed]
... MySQL as the database backend and recently included MongoDB for storing all meta-information of the files, because MongoDB better fits the requirements. For example: photos may have Exif information, videos may have audio-tracks where we to want to store the meta-information of, too. Videos and...
What's the difference between a single precision and double precision floating point operation?
...as the greater data precision available with 64-bit data types is not typically required by 3D games, as well as the fact that processing 64-bit data uses twice as much RAM, cache, and bandwidth, thereby reducing the overall system performance.
From Webopedia:
The term double precision is some...
Func with out parameter
...ss Result
{
public IList<Foo> List { get; set; }
public Int32 Count { get; set; }
}
share
|
improve this answer
|
follow
|
...